Marlene McEwan of Lake Oswego says she lost her husband to lung cancer that was brought on by radon. Their home had levels of 57 picocuries per liter of the radioactive gas. The EPA recommends a homeowner take action fixing a home when the radon level is at or above 4 picocuries per liter of air.

McEwan will be at the HUD announcement today. “This is going to make a large difference to a lot of people,” she said.

Exactly what the new requirements are has yet to be seen. But radon activist Steve Tucker expects that public housing and apartment complexes will now be subject to testing for the naturally-occurring gas.

An earlier version of this story contained incorrect information about radon levels in the home. The EPA website states that there is no known “safe” level of radon exposure. The agency recommends a homeowner take action fixing a home when the radon level is at or above 4 picocuries per liter of air. OPB regrets the error.